153093-72-2Relevant academic research and scientific papers
Substituent-Controlled Divergent Cascade Cycloaddition Reactions of Chalcones and Arylalkynols: Access to Spiroketals and Oxa-Bridged Fused Heterocycles
Chang, Weixing,Kong, Jingyang,Li, Jing,Liu, Lingyan,Wang, Hongkai,Zeng, Tianlong
supporting information, p. 4024 - 4032 (2021/07/12)
Herein, we report substituent-controlled divergent cascade cycloaddition reactions of chalcones and arylalkynols in the presence of PtI2. Depending on the substituent on the chalcone, either spiroketals or oxa-bridged fused heterocycles could be obtained in the ranges of 86–97% and 87–95% yields under identical reaction conditions. Control experiments were carried out to elucidate the origin of the high chemoselectivity. These provide a method for the synthesis of a diverse array of structurally complex oxygen-containing heterocycles. (Figure presented.).
Synthesis of phthalan derivatives via a formal intramolecular 1,3-insertion of rhodium(II) azavinyl carbenes into O[sbnd]Si bond
Deng, Changchang,Duan, Shengguo,Jie, Yuchen,Luo, Huan,Xiang, Qiaoyi,Xu, Ze-Feng
, (2021/08/30)
The first formal intramolecular 1,3-insertion into O[sbnd]Si bond of rhodium(II) azavinyl carbene have been developed, and valuable phthalan derivatives could be synthesized efficiently. In addition, various functional groups could be introduced to the pr
Discovery of a Photoinduced Dark Catalytic Cycle Using in Situ LED-NMR Spectroscopy
Lehnherr, Dan,Ji, Yining,Neel, Andrew J.,Cohen, Ryan D.,Brunskill, Andrew P. J.,Yang, Junyu,Reibarkh, Mikhail
supporting information, p. 13843 - 13853 (2018/10/24)
We report the use of LED-NMR spectroscopy to study the reaction mechanism of a newly discovered photoinduced iron-catalyzed cycloisomerization of alkynols to cyclic enol ethers. By understanding on/off ligand binding to the catalyst, we were able to appro
The Divergent Cascade Reactions of Arylalkynols with Homopropargylic Amines or Electron-Deficient Olefins: Access to the Spiro-Isobenzofuran- b-pyrroloquinolines or Bridged-Isobenzofuran Polycycles
Wang, Lun,Liu, Lingyan,Chang, Weixing,Li, Jing
supporting information, p. 7799 - 7813 (2018/06/18)
Two divergent cascade reactions of arylalkynols with homopropargylic amines or electron-deficient olefins were developed to synthesize the spiro-isobenzofuran-b-pyrroloquinolines or bridged-isobenzofuran heterocycles in good yields, respectively. One reaction actually involved intramolecular 5-endo-dig hydroamination cyclization-protonation of homopropargylic amines to give cycloiminium ions and intramolecular 5-exo-dig hydroalkoxylation cyclization of arylalkynols to generate isobenzofuran with exocyclic double bond, followed by the nontypical Povarov-type reaction in the presence of PtCl2/FeCl3 cocatalysts. The other underwent intramolecular hydroalkoxylation cycloisomerization of alkynols with the subsequent normal [4 + 2] cycoaddition with dienophiles. Herein, the arylalkynols acted as both "masked" electron-rich olefins and "masked" electron-rich dienes.
Synthesis of 5-Iodo-1,2,3,4-tetrahydropyridines by Rhodium-Catalyzed Tandem Nucleophilic Attacks Involving 1-Sulfonyl-1,2,3-triazoles and Iodides
Man, Zengming,Dai, Haican,Shi, Yinping,Yang, Dongdong,Li, Chuan-Ying
supporting information, p. 4962 - 4965 (2016/10/18)
Sodium iodide is used for the first time as a nucleophile to trap an α-imino rhodium carbene, which triggers a tandem process involving intermolecular nucleophilic attack and intramolecular SN2 reaction. A series of 5-iodo-1,2,3,4-tetrahydropyridines are obtained in high yield, and the synthetic utility of the products is demonstrated in cross-coupling reactions and the construction of biorelated polycyclic compounds.
Indium-catalyzed annulation of indoles with ethyl (2-ethynylaryl)methyl carbonates: Synthesis and photoluminescent properties of aryl- and heteroaryl[b]carbazoles
Nagase, Yuta,Miyamura, Takuhiro,Inoue, Kensuke,Tsuchimoto, Teruhisa
supporting information, p. 1170 - 1172 (2013/10/22)
Two successive carbon-carbon bond-forming annulation of indoles with ethyl (2-ethynylaryl)methyl carbonates and their heteroaryl analogs under indium catalysis provided aryl- and heteroaryl[b]carbazoles, photoluminescent properties of which were then eval
Regioselective synthesis and evaluation of 3-alkylidene-1, 3-dihydroisobenzofurans as potential antidepressant agents
Praveen,Iyyappan,Girija,Kumar, K Suresh,Perumal
body text, p. 451 - 462 (2012/08/07)
3-Alkylidene-1,3-dihydroisobenzofurans exhibited moderate antidepressant activity as evaluated by forced swim and tail suspension test methods. Virtual screening was carried out by docking the designed compounds into the serotonin binding sites of arabinase protein to predict the analogue binding mode of the compounds to the SSRIs. [Figure not available: see fulltext.]
Cycloisomerization of aromatic homo and bis-homopropargylic alcohols via catalytic ru vinylidenes: Formation of benzofurans and isochromenes
Varela-Fernandez, Alejandro,Gonzalez-Rodriguez, Carlos,Varela, Jesus A.,Castedo, Luis,Saa, Carlos
supporting information; experimental part, p. 5350 - 5353 (2009/12/30)
Ru-catalyzed cycloisomerizations of aromatic homo- and bis-homopropargylic alcohols effectively afford benzofurans and isochromenes. These processes proved to be chemo- and regioselective (5-, and 6-endo cyclizations) derived from key Ru vinylidene intermediates. The presence of an amine/ammonium base-acid pair is crucial for the catalytic cycle.
An Unusual Example of a 6-Endo-Dig Addition to an Unactivated Carbon-Carbon Triple Bond
Padwa, Albert,Krumpe, Keith E.,Weingarten, M. David
, p. 5595 - 5603 (2007/10/03)
Methyl 2-ethynyl>benzoate was prepared as an intermediate for subsequent conversion to an α-diazo ketone.Under the basic conditions used to hydrolyze the methyl ester, the neighboring hydroxyl functionality underwent reaction with the unactivated acetylenic group, producing a benzopyranyl-substituted α-diazoacetophenone.Treatment of this diazocarbonyl compound with a catalytic quantity of rhodium(II) mandelate afforded a novel dibenzocyclononenone derivative.The reaction proceeds via an initially formed oxonium ylide which rearranges further by means of a 1,2-alkyl shift.A prime factor in determining the direction of internal cyclization to the triple bond is the presence of the carbomethoxy group in the ortho position of the β-phenyl ring.Thus, in contrast with related systems which exhibit a clear preference for 5-exo-dig cyclization at the acetylenic center, the 6-endo-dig addition is the preferred pathway for the o-formyl- and o-carbomethoxy-substituted alkynyl alcohols.Careful monitoring of the reaction actually showed that the reaction proceeds by initial formation of the 5-exo-dig product followed by a novel rearrangement to the 6-endo product.
Synthesis of 11-Membered Enediyne Ketones by the Intramolecular Nicholas Reaction
Maier, Martin E.,Brandstetter, Tilmann
, p. 1009 - 1016 (2007/10/02)
An efficient route to 11-membered enediyne ketones 13 and 22 was developed.This route is based on an intramolecular Nicholas reaction of 11 and 20, respectively.In the course of the preparation of the cyclization substrates 11 and 20, it was important to
